BOSQUE DEL APACHE NATIONAL WILDLIFE REFUGE, N.M. - It's dusk, and a distant rainstorm has left a double rainbow in the late-October sky. I sit near the banks of the Rio Grande, waiting for the sandhill cranes to arrive from the nearby fields where they feed all day. Right now, about 1,000 of them have come to the Bosque del Apache refuge. By mid-November, 10,000 should be here, just in time for the town of Socorro's annual Festival of the Cranes. Here along the river, the birds are relatively safe from nocturnal predators, like the coyotes yipping in the distance.

As daylight fades, the pewter-colored sandhills drop onto one of many shallow ponds, arriving in small groups and chattering to each other excitedly, then emitting high-pitched "purrs" before settling down for the night. I'm mesmerized, but can't shake a feeling of loss, knowing that if attitudes in the West were different, I could also be watching the magnificent, five-foot-tall whooping crane - a rare white bird with black-tipped wings that span more than seven feet.

I'm here with volunteer naturalist Robert Kruidenier, a 56-year-old retired contractor from Santa Fe, who moved to Bosque del Apache four years ago after developing Parkinson's disease. He is one of a handful of New Mexicans who watched the day-to-day lives of the last whooping cranes in the West. There were about a dozen cranes a decade ago; only three remained by 2000. Last year, the single remaining whooping crane west of the Mississippi flew back to New Mexico for one more winter at Casa Colorado, a small marsh north of here. It left last spring, never to be seen again.

Announcement of its death ended more than 25 years of biologists' efforts to recreate a Rocky Mountain flock of whooping cranes. And though I've lived in New Mexico for 14 years, I never saw them. "I'll go next year," I'd say, but ran out of time.

Now, as we watch the sandhill cranes quacking and honking in the reflections of golden cottonwoods, among ducks, geese and shorebirds, I can't help but wonder how the West went wrong for the whoopers.

By some estimates, there were as many as 1,400 whooping cranes in North America when Europeans arrived. But as settlers began moving west, they hunted the cranes, plowed the prairies and drained the marshes. By 1941, only 15 whoopers remained nationwide. In 1967, six years before the Endangered Species Act became law, biologists declared the whooping crane "endangered" and the U.S. Fish and Wildlife Service began an all-out effort to save it from extinction.

In 1975, scientists placed whooping crane eggs underneath nesting sandhill cranes at Gray's Lake Wildlife Refuge in southeastern Idaho. The idea was to have the sandhills raise the whoopers and teach them the ways of migration. Initially, it worked: The sandhills were great surrogate moms, and the birds flew to the Bosque together. But there was one hitch: The whooping cranes wouldn't mate. Biologists had to scrap the "cross-foster" project in 1989. Next, biologists tried pairing wild whooping cranes with captive birds, which looked promising until it came time to migrate. Relationships failed miserably as the wild cranes flew off, leaving their partners behind.

Then, in mid-1997, Idaho biologist and farmer Kent Clegg received federal funding to raise a group of whooping cranes, and, using an Ultralight aircraft, teach them to migrate with his own small flock of sandhills. It was a charismatic project; TV crews followed Clegg in his aircraft - with eight sandhill and four whooping cranes flying alongside - throughout the 850-mile trip from Idaho to the Bosque.

But Clegg's effort was too little, too late, says Tom Stehn, who heads the U.S. Fish and Wildlife Service's national Whooping Crane Recovery Program and was also part of the failed cross-foster project. For years, Stehn had heard complaints about the whoopers, from residents along the Rocky Mountain Flyway in New Mexico, Idaho and Utah. Bird hunters said the federally protected whooping cranes interfered with their right to shoot sandhill cranes. Developers and farmers said they couldn't subdivide farmland or spray crops because of the regulations protecting the bird.

Drought, continued loss of habitat, and a proliferation of people and their power lines - a main source of whooping crane fatalities - doomed the recovery effort. By 1999, the Fish and Wildlife Service moved the recovery effort back east where, Stehn says, people quickly embraced the project. "It's unfortunate we let a natural resource like that go," says Clegg, who believes that the Fish and Wildlife Service caved in to pressures from hunters and developers.

Stehn disagrees. "Populations die. That's what populations do," he counters. While none of the reintroduction programs worked in the West, scientists learned lessons for future work, he says. For one, Stehn says, Ultralights are now helping create a new whooping crane flyway between Wisconsin and Florida.

At Bosque del Apache, the success back East is little consolation. "I miss the whoopers," says Robert Kruidenier, with familial affection, adding that the last crane he saw here, in the fall of 2000, was a female.

"That crane - one of the Ultralight birds - knew it was a whooping crane," he says. When she arrived in 1999, she sought out one of the older cross-foster whooping cranes and the two stayed together all winter long. The old crane was killed when it hit a power line near Alamosa/Monte Vista National Wildlife Refuge in Colorado's San Luis Valley.

The following winter was stressful for the lone female, now four years old and in her reproductive prime. "She was all by herself," Kruidenier says. "She wouldn't stay in one place. She knew there had been one other bird like her the year before, so she kept flying around, hoping to find that one white crane among a sea of gray." She searched until February, when she headed north. When last November rolled around, Kruidenier expected her to return, but she never did.

Only one other whooping crane was left in the West, an older cross-foster bird living in a little-known marshy spot a few miles north of the Bosque. The crane headed north in March but never made it to Montana's Red Rock Lakes Wildlife Refuge, just south of Butte, where it had summered in previous years. While they haven't recovered the body, biologists assume the bird is dead.

Today, there are 415 whooping cranes in the United States; 284 are wild. This spring, in Florida, the first whooping crane was born in the wild since 1939. Biologists nicknamed the chick "Lucky."